Cancer in thirty-nine nuclear industry workers: a preliminary report

We constructed job-exposure profiles and assessed quality of health care in 39 of 47 current and former workers from a nuclear installation in the Negev whose files were referred to us for assessment of a possible work-related aspect of their tumors. The workers, all male except one, began employment at various times from the reactor construction and were engaged in different tasks in laboratory research, construction, maintenance, and service. Of those workers still living the average age was 57.9 years, with a range from 42 to 77 years of age. The average age at the time of death for the deceased workers was 57.3 years, with a range from 41 to 69 years of age, Information on past exposures to radiation and chemical agents came from employee records dosimetry, and interviews. Personal monitoring (urine assays) in 29 workers indicated the presence of various radionuclides, with higher levels found in persons with work histories in laboratory/research and development and technical/inspector job categories compared to those in administrative/service job categories. Among the 39 workers, latency between onset of exposure and first appearance of illness from tumor was 24.2 years, with a range of 5 to 34 years. Tumor distribution for these workers was as follows: hematolymphatic (n = 11 workers), gastrointestinal (n = 9), breast (n = 1 [male]), renal-urogenital (n = 8), skin (n = 1), and pulmonary (n = 8 [5 known smokers]). For all tumors except those of the respiratory tract, the first diagnosis was made more frequently in those patients under the age of 55. Observed/expected comparisons for tumor proportional incidence showed excess fractions of blood tumors in persons < 55 and > 55 years of age. Ratios were greater than unity for blood, breast (n = 1), gastrointestinal, and urogenital tumors in patients < 55 years of age and pulmonary tumors in persons > 55 years of age. The odds ratio for smoking history in patients with lung tumors compared to those with other tumors was 4.8. Nonmalignant conditions appeared at relatively younger ages. After the exposure episodes two children with major congenital anomalies were born to wives of the workers; one anomaly was fatal. Not all patients were first diagnosed for cancer following referral from the plant medical service, and delays between warning signs and symptoms and medical evaluation occurred in some. Although we lacked data on cancer incidence and population at risk, our findings suggest that earlier official assessments of risk should be reconsidered. There is a need for population-based monitoring of risk to nuclear industry workers, external quality control of their medical surveillance and care, and improvements in information delivery.